Is global warming for real?

April 7, 2006

Dear Cecil:

Robert Essenhigh, a professor of mechanical engineering at Ohio State, has written an essay disputing the idea that human activity is causing global warming. He is part of an academic group that opposes the Kyoto treaty. Although I have a PhD in physical organic chemistry and have done some work in environmental areas, I cannot dismiss his arguments out of hand. Is Professor Essenhigh right and can we all go out and buy SUVs? Or are there convincing arguments to the contrary? With the Kyoto treaty on the rocks, it'd be nice to know.

— Jon Kapecki, Rochester, New York

Cecil replies:

I get a lot of letters like yours, Jon, basically asking me, a weekly alternative newspaper columnist, to resolve one of the great controversies of our age. Hey, somebody's gotta do it. However, given an 800-word limit, you'll excuse my taking a few shortcuts. So here we go: Are greenhouse-gas emissions from our fuel-guzzling cars, power plants, etc, a significant contributor to potentially catastrophic climate change? Answer: Beats me. But you know what? It doesn't matter even if they are.

We'll start with Essenhigh. The professor argued in a 2001 article in Chemical Innovation that average global temperatures were rising but that, contrary to wide popular and scientific opinion, human activity wasn't the principal cause. Rather, the fluctuations we're now seeing are part of a natural cycle that's been going on for eons. Essenhigh's reasoning appealed largely to common sense: Carbon dioxide, the most widely discussed greenhouse gas, is part of earth's vast store of carbon (about 150 billion tons), which is continually being cycled through the oceans, the atmosphere, and vegetation. The human contribution to atmospheric carbon in the form of CO2 is small, less than 5 percent of the total carbon reservoir. Ergo, humans aren't causing global warming. I omit a lot of ancillary discussion, but that's the nub.

One might raise scientific objections to this reasoning, but what's the point? Fact is, little can be done to reduce CO2 emissions regardless of their impact on the environment. CO2 isn't just an incidental result of human activity that you can get rid of with smokestack scrubbers. Rather, it's an inherent product of the combustion of carbon-based fuels such as coal and oil. The only practical way to produce less in the short term is to use less organic fuel. (Long term we'll switch to nukes, solar, wind, and other non-carbon-emitting energy sources, plus biofuels, where the carbon in- and outputs are a wash. In addition, carbon sequestration technologies may enable us to pull excess carbon out of the atmosphere.)

That brings us to the Kyoto Protocol to the United Nations Framework Convention on Climate Change, which the U.S. has famously refused to ratify. Kyoto calls for drastic cuts in emissions of CO2 and other greenhouse gases — 5.2 percent below 1990 levels, or 29 percent below projected 2010 levels. These numbers alone suggest the implausibility of the goal. To brutally oversimplify, greenhouse-gas emissions = energy use = economic activity. (To repeat, I'm speaking short-term.) To produce significantly fewer emissions now, your one choice is to shrink your economy, i.e., become poorer. (Russia, to cite a grim example, is among the few industrialized nations that can meet its Kyoto target due to its economic collapse since 1990.)

Some object to such pessimism. They say that better technology, a modicum of belt-tightening, and purchases of "international emissions permits" (countries exceeding their CO2 reduction targets can sell the difference to those that don't) will enable many countries to meet their Kyoto goals.

Hey, anything's possible. But here's the thing. Even if all Kyoto targets are met, world carbon emissions will continue to rise. Why? Because Kyoto exempts developing nations, and increased carbon emissions in those countries will swamp any reductions the developed world achieves.

Evidence on this score comes to us from International Energy Outlook 2005, a publication of the U.S. Department of Energy's Energy Information Administration. The EIA projects that world carbon dioxide emissions will increase more than 50 percent between 2002 and 2025, from 24 billion to 39 billion metric tons (IEO 2005, table 10). If the industrialized nations participating in the Kyoto Protocol ("Annex I" countries) achieve their goals, the EIA projects that by 2025 their CO2 emissions will be reduced by only 0.6 billion tons (IEO 2005, table 12). Meanwhile, emissions in developing countries will increase nearly ten billion tons. In short, we're going to see a huge jump in emissions no matter what industrialized nations do.

Is the solution, then, to rein in the developing nations? Hardly. While we can advise countries such as China and India on ways to use energy more efficiently, we can't seriously expect them to halt their efforts to achieve the prosperity we already have — and make no mistake, it's precisely those efforts that are driving up carbon emissions. China alone supposedly expects to add 15,000 megawatts of electric power capacity every year.

So, if nothing can be done to reduce CO2, should we quit worrying, buy SUVs, and party on? On the contrary. Fossil fuels are to the developing world today what the American forest was to this country two centuries ago — a cheap, easily exploited resource that permits extraordinary economic growth for the short time that it lasts. The U.S., through its huge trade deficits and job exports, is now financing the industrialization of Asia, a result we didn't intend but may as well make the most of — clearly we want teeming nations like China, India, and Indonesia to become prosperous, stable societies.

Making that happen, though, will take decades of steady investment and jigawatts of energy, the price of which will climb steeply once fossil fuels run out. Hastening that none-too-distant day through frivolous use of the supplies we now have would be stupid (although fossil fuel depletion will also end the emissions problem). A more realistic approach is to say, OK, we're going to burn this fuel and cope with whatever dire result, but let's put the stuff to good use while we've got it. That means distributing improved technology to use energy more efficiently and pollute less. Amazingly, just such an approach was agreed to last year when the U.S., Australia, China, India, Japan, and South Korea formed the Asia-Pacific Partnership on Clean Development and Climate, which may go down as Dubya's saving grace after having screwed the pooch in Iraq.